4ms Shaped Dual EnvVCA User manual

Shaped Dual EnvVCA
4ms Company
User Manual 1.0 – November 15, 2022
The Shaped Dual EnvVCA is a dual analog envelope generator, waveshaper, slew limiter, and VCA.
Each of the two channels is identical and they can be used separately or together.
Shaped Dual EnvVCA features:
•Versatile linear, exponential, and logarithmic envelope generator/LFO
•Low-noise, low-distortion, DC-coupled linear VCAs
•Shape slider, CV jack and attenuverters for fading between Exponential, Linear, and Logarithmic
envelope shapes without changing envelope timing
•100% analog
•Sliders and range switches control Rise and Fall times from ~2ms (500Hz) to ~2 min.
•Time CV jack extends time range: ~400µs (2.5kHz) to ~1 hour.
•Independent attenuverters for Rise and Fall time
•Blue/Red lights indicate strength and polarity
•Cycle buttons for looping envelopes (LFO)
•Trigger input jack and switch for toggling between AR, ASR, and Cycle modes of triggering
•EOR/F (End of Rise/Fall) gate outputs can be used to chain and sequence events
•Env Level and Offset knobs scale and shift ENV output without changing VCA volume
•Audio In and Out jacks for passing audio or CV through the VCA
•VCA CV inputs to use VCAs independently from the envelopes
•VCA gain internally connected to envelope output when VCA CV jack is left unpatched
•Follow input jacks allow for slew limiting, envelope following/sidechaining, ADSR, and exotic
filtering effects
• Re-trig jumpers allow for re-triggering during rise phase
Cycle
AR
ASR
Cycle
AR
ASR
Rise Fall
Shaped Dual EnvVCA
TimeTime
Follow
VCA CVVCA CV
In
Audio BAudio A
Out
In
Out Lin 5VLin 5V
OR
Shape
Rise Fall
Slow
Fast
Med
Slow
Fast
Trig Cycle
Offset
Level
EOF
Fall
Rise
Shape Shape
Follow
ENV A ENV B
Shape
FallRise
Slow
Fast
Med
Slow
Fast
Trig
Cycle
Offset
Level
EOR A

Table of Contents
Setting up your Shaped Dual EnvVCA! "...................................................................3
Controls and Jacks! "................................................................................................3
Rise and Fall Time Ranges! "....................................................................................6
Patch: Making Notes! ".............................................................................................7
Making Notes (basic)! ".......................................................................................7
Making Notes in Stereo! "...................................................................................7
Synchronizing channels: Making Notes Using Triggers! "...................................8
Creating Stereo Motion! "....................................................................................8
Using a Keyboard or Sequencer! "......................................................................9
Patch: Waveshaping! "............................................................................................10
Modulating Waveshape! ".................................................................................10
Different Waveshapes for Rise and Fall! "...............................................................11
Log Rise with Expo Fall! ".................................................................................11
Any Combination of Shapes! "..........................................................................11
Patch: Modulating Time! ".......................................................................................12
Rapid Bursts! "..................................................................................................12
Ratcheting! "......................................................................................................12
Patch: Making an Oscillator and Synth Drums! "....................................................13
Making an Oscillator! "......................................................................................13
Making a Kick Drum! ".......................................................................................13
Making other Synth Drum sounds! ".................................................................14
Self-patching ideas! "..............................................................................................15
Frequency Modulation (FM)! "...........................................................................15
Chaotic FM! "....................................................................................................15
Utility Patches! "......................................................................................................15
Attenuator! "......................................................................................................15
Trigger Delay with Pulse Width control! "..........................................................15
Inverted Trigger Delay (With Pulse Width Control)! ".........................................15
DC generator (Manual CV)! ".............................................................................15
Creating Envelopes with Trig Jack and Switch, Cycle Button, and Follow Jack! ".16
Triggering with switch set to AR! "....................................................................16
Triggering with switch set to ASR! "..................................................................16
Triggering with RETRIG Jumper Off (Factory Default)! "...................................16
Triggering with RETRIG Jumper On! "...............................................................16
Cycle Button and Triggering with switch set to Cycle! "...................................16
Follow Jack with Gates! "..................................................................................17
Fundamentals of the Follow Jack! "........................................................................17
Audio filter! "......................................................................................................18
Portamento/glide! "...........................................................................................18
Sidechaining (Envelope Following)! "................................................................18
Using non-linear Shapes with Follow! "............................................................19
Creating ADSR Envelopes! "...................................................................................20
ADSR envelope! "..............................................................................................20
Table of Envelope Shapes! "...................................................................................22
Using Offset and Level Knobs! ".............................................................................23
RETRIG Jumper! "...................................................................................................23
Electrical and Mechanical Specifications!............................................................24
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Setting up your Shaped Dual EnvVCA
1. Power off your Eurorack system.
2. On the back of the Shaped Dual EnvVCA you will see a 10-pin header. The 10-
pin header connects to a Eurorack power header using the included power
cable. Connect the 16-pin end of the power cable to a 16-pin Eurorack power
header on your power supply distribution board and the 10-pin end to the
Shaped Dual EnvVCA with the red stripe on the power cable oriented towards
the bottom of the module.
3. Using the included screws, securely attach the Shaped Dual EnvVCA to the
rails of your case.
4. Power on your Eurorack system.
Note: The Shaped Dual EnvVCA is reverse-polarity protected, but incorrectly
connecting any module in any system can damage other modules on the power bus.
Controls and Jacks
Cycle Buttons
The Cycle buttons toggle the cycling state for each channel. When cycling,
the Shaped Dual EnvVCA behaves like an LFO, with an output waveform
that continuously rises and falls. Each button illuminates orange to indicate
the module is cycling. Note that pressing this button does not reset or alter an
envelope that’s already rising or falling.
Cycling can also be toggled with a gate signal using the Trig jack and switch
(see below).
Rise/Fall Sliders and Switches
The Rise and Fall sliders control the rise and fall times of the envelope.
Moving a slider up makes the rise or fall portion slower, moving it down
makes it faster.
Each slider has a white light that indicates the current stage and output level
of the envelope. When the envelope is in the rise stage, the Rise slider light
will increase in brightness until the envelope hits its maximum. Once the peak
is reached, the Rise light will turn off and the Fall light will turn on, decreasing
in brightness as the envelope falls.
The Rise/Fall switches select the overall range of the sliders. Each slider has
its own switch with three positions: Fast, Med, Slow.
When the switch is flipped to Fast, the envelopes go well into the audio
range, allowing for classic AM, FM, and other fast modulation effects.
The middle position (Med)is designed for typical musical tempos, and can be
useful when using the VCA to make notes at common BPMs.
The Slow position is geared for gradual fades and other slow LFO-style
modulations.
See the Rise and Fall Time Ranges chart on page 6 for more information.
Time CV Jack and Rise/Fall CV Knobs
The Time CV jack modulates the Rise and Fall times of the envelope. The
jack feeds two knobs: Rise CV, and Fall CV. Each of these knobs is an
attenuverter (short for “attenuating inverter”) and controls how much the
control voltage on the Time CV jack will affect the rise or the fall time.
Turning an attenuverter knob to the right of center means that a positive
voltage on the Time CV jack will lengthen the rise/fall time and a negative
voltage will shorten the rise/fall time.
Turning a knob to the left of center gives the opposite effect, meaning that a
positive voltage on the Time CV jack will shorten the the rise/fall time, while a
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Cycle
FallRise
Slow
Fast
Med
Slow
Fast
Time
Fall
Rise

negative voltage will lengthen these durations.
The farther you turn the knob from center in either direction, the more effect
incoming CV will have. When the knob is centered, the signal on the Time
CV jack will have no effect on the rise or fall time.
Next to each knob is a light which indicates the strength and polarity of the
modulation. The light will turn blue when the rise or fall time is being
lengthened by CV, and red when the time is being shortened. The brighter the
light, the more of an effect the CV is having. When the light is off, the Time
CV jack has no effect on the envelope time.
When nothing is plugged into the Time CV jack, the knobs act as fine-tuning
controls for the Rise and Fall times.
Shape Sliders and Lights
The Shape sliders smoothly crossfade between three different envelope
shapes: exponential, linear and logarithmic, as indicated by the graphic
above each slider. Changing the waveshape does not affect the rise or fall
times. The color of the light above the slider indicates the current wave
shape: green for exponential, red for linear, blue for logarithmic. Intermediate
wave shapes are represented by a blend of these colors. The white light on
the slider indicates the amplitude of the envelope, independent of the
envelope Level and Offset settings.
Shape Jack and Shape Knob
Patching a CV signal into the Shape jack will control the waveshape of the
envelope. The Shape knob is an attenuverter and controls how much the
voltage on the Shape jack will change the envelope shape. When the Shape
knob is to the right of center, positive voltage on the jack will cause the shape
to become more logarithmic, while negative voltage will cause the shape to
become more exponential. If the knob is to the left of center, the relationship
is inverse. The farther from center the knob is positioned, the more effect
incoming CV will have. When the knob is centered, CV on the jack will have
no effect. When using the Shape knob or jack in combination with the Shape
slider, the slider acts as a voltage offset. The Shape jack, knob, and slider
can be used together to create waveforms with different shapes for the rise
and fall segments. See Different Waveshapes for Rise and Fall on page 11
for more details.
ENV, Lin 5v, and OR Jacks
The ENV jacks output the waveshaped envelope for each channel. DC offset
and vertical scale are determined by the positions of the Level and Offset
knobs. Envelope shape is determined by the positions of the Shape slider
and knob as well as CV applied to the Shape CV jack. The OR jack
compares each side's ENV output signals and outputs the highest voltage
value between the two at any given moment. The lights indicate the
amplitude and polarity of each envelope. When the envelope is a positive
voltage, its respective light will shine blue. When the envelope is a negative
voltage, the light will shine red. The brightness of each light indicates the
amplitude and offset of the outgoing signal, so when the light is off, this
means the signal is outputting at or around 0V. The Lin 5V jacks output a
linear waveshape from 0V to +5V, independent of Level, Offset, or Shape
settings.
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Lin 5VLin 5V
OR
ENV A ENV B
Shape
Shape

Env. Level and Offset Knobs
The Level knob attenuates and inverts (attenuverts) the envelope output on
each Env Out jack. When Offset is centered, turning Level fully clockwise
will output a positive envelope, with a maximum peak of about 10V. Turning
the knob counter-clockwise inverts the envelope; when fully counter-
clockwise, the output will peak at about -10V.
Turning the Offset knob clockwise will add a positive DC offset between 0V
and 10V to the envelope, while turning the knob counter-clockwise will add a
negative offset between 0V and -10V. See Using Level and Offset on page 23
for more details.
Note that neither the Level nor the Offset knobs affect the envelope going to
the internal VCAs. For example, if the ENV output jack is patched to a
modulation input on an external module while audio is running through the
VCA, Level and Offset can be used to control the amount of modulation
without changing the audio level or Lin 5V envelope signal.
Audio In, Audio Out, and VCA CV Jacks
The Audio In and Out jacks are the input and output of the VCA. The
waveshaped envelope output (pre-Level and Offset knobs) is internally
routed to the VCA CV input. When the envelope is stopped or at 0V, the Out
jack will output silence. As the envelope rises, the signal will get louder until it
becomes as loud as the input signal at the peak of the envelope. As the
envelope falls, the signal will fade back to silence. Audio In Bis normalized
to Audio In A, as indicated by the graphics on the faceplate. So when Audio
In B is unpatched, the Audio In A signal will be sent to both channels.
Patching into Audio In B will break this connection so that both channels are
operating independently. The VCA is normalized to the waveshaped
envelope, so adjusting the Shape slider and CV will affect the VCA.
When patched, the VCA CV jacks break the internal connection between
envelope and VCA, allowing for independent use of the VCA. The VCA CV
input has a range of 0 to 5V, which translates to nearly silent to unity gain.
The VCA has a linear response to the VCA CV, meaning that the voltage on
the VCA CV jack directly sets the attenuation amount (e.g. 2.5V is about 50%
attenuation).
Trig Jacks and Switches (Cycle, AR, ASR)
The Trig input jack and switch can be used with both gates and triggers in
order to generate envelopes. The trigger switch selects the function of the
jack: Cycle, AR or ASR.
When the switch is centered at AR (Attack Release), a trigger will initiate a
single complete envelope if there is no envelope in progress. If the envelope
is rising when a trigger is received, then the trigger is ignored (unless the
RETRIG jumper is installed, see below). If the envelope is falling while a
trigger is received, it will begin rising from its current voltage.
When the switch is flipped down to ASR (Attack Sustain Release), the
envelope will behave similarly to AR mode, but will remain high for as long as
the gate on the Trig jack remains high. Once the gate goes low, the envelope
will switch to its release stage and begin falling. The envelope will always
complete a full rise and fall stage, even if the gate goes low before the rise
stage is done.
When the switch is flipped up to Cycle, a gate toggles the cycle state. If the
Cycle button is off, a gate signal will turn the button on and make the channel
cycle for as long as the gate is held high. If the Cycle button is on, then a
gate signal will turn the button off and cease any cycling for as long as the
gate is held high. See Cycle Button on page 16 for more information.
On the back of the module is a RETRIG jumper for each channel. When this
jumper is installed, the envelope will immediately jump to 0V and start rising
any time a trigger is received (regardless of the switch position). This can
cause a click on the VCA output, so the jumper is not installed at the factory.
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Level
Offset
VCA CV
In
Audio B
Out
A
Cycle
AR
ASR
Trig